BlackTreeCVE Intelligence
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Full vulnerability report · 2021
CVE-2021-33033High confidence

n/a — Use After Free

Unknown · Unknown

7.8HighCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:High, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • A structured source references public exploit or proof-of-concept material.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.57% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs Unknown Unknown and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 30 daysRemediation target: Within 180 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

5 package states
Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 1 affected package state shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.24-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.24-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.24-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.10.24-1Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical Ubuntu Security ↗Source updated 5 Oct 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-19753

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

The Linux kernel before 5.11.14 has a use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c because the CIPSO and CALIPSO refcounting for the DOI definitions is mishandled, aka CID-ad5d07f4a9cd. This leads to writing an arbitrary value.

What

The Linux kernel before 5.11.14 has a use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c because the CIPSO and CALIPSO refcounting for the DOI definitions is mishandled, aka CID-ad5d07f4a9cd. This leads to writing an arbitrary value.

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

The Linux kernel before 5.11.14 has a use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c because the CIPSO and CALIPSO refcounting for the DOI definitions is mishandled, aka CID-ad5d07f4a9cd. This leads to writing an arbitrary value.

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path
local access → Use After Free → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-416 ↗

CWE-416: Use After Free. The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
CWE-416Public exploit reference
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2023-0063Juniper Junos Space: Mehrere Schwachstellen

Ein Angreifer aus dem angrenzenden Netzwerk oder ein entfernter anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Juniper Junos Space ausnutzen, um Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand auszulösen, beliebigen Code auszuführen und seine Privilegien zu erweitern.

Official advisory ↗
BSI · German · WID-SEC-2024-1591Juniper JUNOS: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20210519Security Bulletin 19 May 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 19 May 2021, published on 19 May 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0575Multiples vulnérabilités dans les produits Juniper Networks

ord?id=CVE-2021-26691 Référence CVE CVE-2021-27290 https://www.cve.org/CVERecord?id=CVE-2021-27290 Référence CVE CVE-2021-29469 https://www.cve.org/CVERecord?id=CVE-2021-29469 Référence CVE CVE-2021-30641 https://www.cve.org/CVERecord?id=CVE-2021-30641 Référence CVE CVE-2021-31535 https://www.cve.org/CVERecord?id=CVE-2021-31535 Référence CVE CVE-2021-31618 https://www.cve.org/CVERecord?id=CVE-2021-31618 Référence CVE CVE-2021-3177 https://www.cve.org/CVERecord?id=CVE-2021-3177 Référence CVE CVE-2021-32803 https://www.cve.org/CVERecord?id=CVE-2021-32803 Référence CVE CVE-2021-32804 https://www.cve.org/CVERecord?id=CVE-2021-32804 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-33034 https://www.cve.org/CVERecord?id=CVE-2021-33034 Référence CVE CVE-2021-33193 https://www.cve.org/CVERecord?id=CVE-2021-33193 Référence CVE CVE-2021-3347 https://www.cve.org/CVERecord?id=CVE-2021-3347 Référence CVE CVE-2021-33909 https://www.cve.org/CVERecord?id=CVE-2021-33909 Référence CVE CVE-2021-34798 https://www.cve.org/CVERecord?id=CVE-2021-34798 Référence CVE CVE-2021-35604 https://www.cve.org/CVERecord?id=CVE-2021-35604 Référence CVE CVE-2021-35624 https://www.cve.org/CVERecord?id=CVE-2021-35624 Référence CVE CVE-2021-36160 https://www.cve.org/CVERecord?id=CV

Official advisory ↗
CERT-FR · French · CERTFR-2023-AVI-0051Multiples vulnérabilités dans les produits Juniper

ecord?id=CVE-2021-27364 Référence CVE CVE-2021-27365 https://www.cve.org/CVERecord?id=CVE-2021-27365 Référence CVE CVE-2021-28950 https://www.cve.org/CVERecord?id=CVE-2021-28950 Référence CVE CVE-2021-29154 https://www.cve.org/CVERecord?id=CVE-2021-29154 Référence CVE CVE-2021-29650 https://www.cve.org/CVERecord?id=CVE-2021-29650 Référence CVE CVE-2021-30465 https://www.cve.org/CVERecord?id=CVE-2021-30465 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Référence CVE CVE-2021-3177 https://www.cve.org/CVERecord?id=CVE-2021-3177 Référence CVE CVE-2021-32399 https://www.cve.org/CVERecord?id=CVE-2021-32399 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-33034 https://www.cve.org/CVERecord?id=CVE-2021-33034 Référence CVE CVE-2021-3347 https://www.cve.org/CVERecord?id=CVE-2021-3347 Référence CVE CVE-2021-33909 https://www.cve.org/CVERecord?id=CVE-2021-33909 Référence CVE CVE-2021-3450 https://www.cve.org/CVERecord?id=CVE-2021-3450 Référence CVE CVE-2021-34798 https://www.cve.org/CVERecord?id=CVE-2021-34798 Référence CVE CVE-2021-3504 https://www.cve.org/CVERecord?id=CVE-2021-3504 Référence CVE CVE-2021-35550 https://www.cve.org/CVERecord?id=CVE-2021-35550 Référence CVE CVE-2021-35556 https://www.cve.org/CVERecord?id=CVE-20

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-264Multiples vulnérabilités dans le noyau Linux de Debian

d?id=CVE-2021-20322 Référence CVE CVE-2021-22600 https://www.cve.org/CVERecord?id=CVE-2021-22600 Référence CVE CVE-2021-28711 https://www.cve.org/CVERecord?id=CVE-2021-28711 Référence CVE CVE-2021-28712 https://www.cve.org/CVERecord?id=CVE-2021-28712 Référence CVE CVE-2021-28713 https://www.cve.org/CVERecord?id=CVE-2021-28713 Référence CVE CVE-2021-28714 https://www.cve.org/CVERecord?id=CVE-2021-28714 Référence CVE CVE-2021-28715 https://www.cve.org/CVERecord?id=CVE-2021-28715 Référence CVE CVE-2021-28950 https://www.cve.org/CVERecord?id=CVE-2021-28950 Référence CVE CVE-2021-29264 https://www.cve.org/CVERecord?id=CVE-2021-29264 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-3640 https://www.cve.org/CVERecord?id=CVE-2021-3640 Référence CVE CVE-2021-3744 https://www.cve.org/CVERecord?id=CVE-2021-3744 Référence CVE CVE-2021-3752 https://www.cve.org/CVERecord?id=CVE-2021-3752 Référence CVE CVE-2021-3760 https://www.cve.org/CVERecord?id=CVE-2021-3760 Référence CVE CVE-2021-3764 https://www.cve.org/CVERecord?id=CVE-2021-3764 Référence CVE CVE-2021-3772 https://www.cve.org/CVERecord?id=CVE-2021-3772 Référence CVE CVE-2021-38300 https://www.cve.org/CVERecord?id=CVE-2021-38300 Référence CVE CVE-2021-39685 https://www.cve.org/CVERecord?id=CVE-2021-396

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-265Multiples vulnérabilités dans le noyau Linux de Ubuntu

d?id=CVE-2021-28688 Référence CVE CVE-2021-28711 https://www.cve.org/CVERecord?id=CVE-2021-28711 Référence CVE CVE-2021-28712 https://www.cve.org/CVERecord?id=CVE-2021-28712 Référence CVE CVE-2021-28713 https://www.cve.org/CVERecord?id=CVE-2021-28713 Référence CVE CVE-2021-28714 https://www.cve.org/CVERecord?id=CVE-2021-28714 Référence CVE CVE-2021-28715 https://www.cve.org/CVERecord?id=CVE-2021-28715 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29650 https://www.cve.org/CVERecord?id=CVE-2021-29650 Référence CVE CVE-2021-32399 https://www.cve.org/CVERecord?id=CVE-2021-32399 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-33034 https://www.cve.org/CVERecord?id=CVE-2021-33034 Référence CVE CVE-2021-33098 https://www.cve.org/CVERecord?id=CVE-2021-33098 Référence CVE CVE-2021-34693 https://www.cve.org/CVERecord?id=CVE-2021-34693 Référence CVE CVE-2021-3483 https://www.cve.org/CVERecord?id=CVE-2021-3483 Référence CVE CVE-2021-3506 https://www.cve.org/CVERecord?id=CVE-2021-3506 Référence CVE CVE-2021-3564 https://www.cve.org/CVERecord?id=CVE-2021-3564 Référence CVE CVE-2021-3573 https://www.cve.org/CVERecord?id=CVE-2021-3573 Référence CVE CVE-2021-3612 https://www.cve.org/CVERecord?id=CVE-2021-

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-923Multiples vulnérabilités dans le noyau Linux de SUSE

ERecord?id=CVE-2020-14305 Référence CVE CVE-2020-3702 https://www.cve.org/CVERecord?id=CVE-2020-3702 Référence CVE CVE-2020-4788 https://www.cve.org/CVERecord?id=CVE-2020-4788 Référence CVE CVE-2021-0941 https://www.cve.org/CVERecord?id=CVE-2021-0941 Référence CVE CVE-2021-20265 https://www.cve.org/CVERecord?id=CVE-2021-20265 Référence CVE CVE-2021-20320 https://www.cve.org/CVERecord?id=CVE-2021-20320 Référence CVE CVE-2021-20322 https://www.cve.org/CVERecord?id=CVE-2021-20322 Référence CVE CVE-2021-22543 https://www.cve.org/CVERecord?id=CVE-2021-22543 Référence CVE CVE-2021-31916 https://www.cve.org/CVERecord?id=CVE-2021-31916 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-34556 https://www.cve.org/CVERecord?id=CVE-2021-34556 Référence CVE CVE-2021-34981 https://www.cve.org/CVERecord?id=CVE-2021-34981 Référence CVE CVE-2021-3542 https://www.cve.org/CVERecord?id=CVE-2021-3542 Référence CVE CVE-2021-35477 https://www.cve.org/CVERecord?id=CVE-2021-35477 Référence CVE CVE-2021-3640 https://www.cve.org/CVERecord?id=CVE-2021-3640 Référence CVE CVE-2021-3653 https://www.cve.org/CVERecord?id=CVE-2021-3653 Référence CVE CVE-2021-3655 https://www.cve.org/CVERecord?id=CVE-2021-3655 Référence CVE CVE-2021-3656 https://www.cve.org/CVERecord?id=CVE-2021-

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-916Multiples vulnérabilités dans le noyau Linux de SUSE

ERecord?id=CVE-2020-12770 Référence CVE CVE-2020-36385 https://www.cve.org/CVERecord?id=CVE-2020-36385 Référence CVE CVE-2020-3702 https://www.cve.org/CVERecord?id=CVE-2020-3702 Référence CVE CVE-2020-4788 https://www.cve.org/CVERecord?id=CVE-2020-4788 Référence CVE CVE-2021-0941 https://www.cve.org/CVERecord?id=CVE-2021-0941 Référence CVE CVE-2021-20265 https://www.cve.org/CVERecord?id=CVE-2021-20265 Référence CVE CVE-2021-20322 https://www.cve.org/CVERecord?id=CVE-2021-20322 Référence CVE CVE-2021-22543 https://www.cve.org/CVERecord?id=CVE-2021-22543 Référence CVE CVE-2021-31916 https://www.cve.org/CVERecord?id=CVE-2021-31916 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-33909 https://www.cve.org/CVERecord?id=CVE-2021-33909 Référence CVE CVE-2021-34556 https://www.cve.org/CVERecord?id=CVE-2021-34556 Référence CVE CVE-2021-34981 https://www.cve.org/CVERecord?id=CVE-2021-34981 Référence CVE CVE-2021-3542 https://www.cve.org/CVERecord?id=CVE-2021-3542 Référence CVE CVE-2021-35477 https://www.cve.org/CVERecord?id=CVE-2021-35477 Référence CVE CVE-2021-3609 https://www.cve.org/CVERecord?id=CVE-2021-3609 Référence CVE CVE-2021-3640 https://www.cve.org/CVERecord?id=CVE-2021-3640 Référence CVE CVE-2021-3653 https://www.cve.org/CVERecord?id=CVE-202

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-893Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, une atteinte à l'intégrité des données et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-886Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, un déni de service et une atteinte à l'intégrité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-880Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Elles permettent à un attaquant de provoquer une atteinte à l'intégrité des données, un déni de service et une élévation de privilèges.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-869Multiples vulnérabilités dans SUSE le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans SUSE le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, une exécution de code arbitraire et un déni de service.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-859Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, un déni de service et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-573Multiples vulnérabilités dans le noyau Linux de Red Hat

De multiples vulnérabilités ont été découvertes dans le noyau Linux de Red Hat. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, un contournement de la politique de sécurité et une atteinte à l'intégrité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-436Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2021-28964 Référence CVE CVE-2021-28971 https://www.cve.org/CVERecord?id=CVE-2021-28971 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29155 https://www.cve.org/CVERecord?id=CVE-2021-29155 Référence CVE CVE-2021-29264 https://www.cve.org/CVERecord?id=CVE-2021-29264 Référence CVE CVE-2021-29647 https://www.cve.org/CVERecord?id=CVE-2021-29647 Référence CVE CVE-2021-30002 https://www.cve.org/CVERecord?id=CVE-2021-30002 Référence CVE CVE-2021-31829 https://www.cve.org/CVERecord?id=CVE-2021-31829 Référence CVE CVE-2021-31916 https://www.cve.org/CVERecord?id=CVE-2021-31916 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-33200 https://www.cve.org/CVERecord?id=CVE-2021-33200 Référence CVE CVE-2021-3483 https://www.cve.org/CVERecord?id=CVE-2021-3483 Référence CVE CVE-2021-3501 https://www.cve.org/CVERecord?id=CVE-2021-3501 Gestion détaillée du document le 07 juin 2021 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systèm

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-432Multiples vulnérabilités dans le noyau Linux d'Ubuntu

De multiples vulnérabilités ont été découvertes dans le noyau Linux d'Ubuntu. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire, un déni de service et une atteinte à l'intégrité des données.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-001912Linux Kernel における解放済みメモリの使用に関する脆弱性

Linux Kernel には、解放済みメモリの使用に関する脆弱性が存在します。 ベンダは、本脆弱性を CID-ad5d07f4a9cd として公開しています。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
n/a
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 14 May 2021 · Last source change 3 Aug 2024, 23:42 UTC · CWE-416 · Use After Free

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-19753
Product sourceUnavailable
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD enriched

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-19753↗CVE authority or vendor reference↗Patch or update reference↗Patch or update reference↗Patch or update reference↗Public exploit reference↗Public exploit reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-33033 · cve.blacktree.nl